Thinly slice potatoes. Line a pie plate or casserole dish with bacon, leaving half slices of bacon over the edge of dish. Layer potatoes, a generous amount of grated cheese, chopped chives, and salt and pepper to taste. 

Repeat until you have four layers. Sprinkle first layer only with ground thyme. Pull bacon up over top of pie. Pie should be 4-5 inches thick. Fasten center of pie with skewer.

Cover with plastic wrap, then cover over top with foil and bake at 400°F for 2 hours. Remove plastic wrap and continue to bake for another 30 minutes until fork tender and the bacon is cooked. 

Sauce: In a medium bowl, combine all sauce ingredients. Serve over cooked potato pie.